Before I answer your question, please confirm with BOA that if you use the enclosed check and deposit $4,500 into your check account, the promotion rate will apply, not the cash advance rate.

Assuming the 0% applies and you only use one check to deposit the $4,500, the actual cost of this promotion is approximately $108 - the transaction fee of $90, compounded one year at an estimated normal APR rate of 20%. Unfortunately, your monthly payment will go towards paying off your 0% balance first, not the normal APR transaction fee.

Also, you will still need to make monthly minimum payments (anywhere from $60 - $200) to keep the good standing of the offer. Should you default on the loan, the promotional rate may be revoked by the credit card company.